General Description

The Multilin 469 Motor Management Relay is an advanced protection, control, and monitoring device designed for medium- and high-power motors. It integrates comprehensive electrical and thermal protection, real-time measurement, diagnostics, and communication functions into a single platform.

The relay is widely used in critical industrial motor applications and can be seamlessly integrated with DCS and control systems such as GE Mark VIe, Siemens S7, and other industrial automation platforms.

Electrical Inputs and Power Supply

Phase current input:

5 A CT secondary (P5 identification)

Control power supply:

90–300 VDC

70–265 VAC, 48–62 Hz

(HI identification)

Analog and Digital I/O

Analog outputs:

4 × 4–20 mA analog outputs (A20 option)

Digital I/O:

8 configurable digital inputs/outputs

Relay outputs:

4 programmable output relays

Contact rating:

250 VAC / 5 A

30 VDC / 5 A

Temperature Measurement

RTD inputs:

Supports 3-wire RTDs

Pt100, Ni100, and equivalent types

Typical usage:

Motor winding temperature monitoring

Bearing temperature monitoring

Thermal data is integrated into motor thermal models for accurate protection and life estimation.

Communication Interfaces

Standard interfaces:

RS-232

RS-485 (Modbus RTU)

Optional interface:

Ethernet (10Base-T)

Supports connection to supervisory systems for monitoring, diagnostics, and data logging.

Core Protection Functions
Electrical Protection

Overcurrent and overload protection (voltage-dependent curves)

Locked rotor and underload protection

Phase loss, phase imbalance, and phase reversal protection

Ground fault protection

Broken rotor bar detection

Thermal and Mechanical Protection

Motor winding temperature protection (RTD-based)

Bearing temperature protection (RTD-based)

Torque measurement and torque protection

Power Quality and Operational Protection

Undervoltage and overvoltage protection

Abnormal frequency protection

Motor start-up timeout protection

These functions ensure comprehensive protection during start-up, normal operation, and abnormal system conditions.

Monitoring and Diagnostics

Real-time motor electrical and thermal measurements

Built-in self-diagnostics for relay health monitoring

Event recording and fault logs for post-fault analysis

Supports detailed operational data retrieval via software tools

Configuration and Maintenance

Firmware upgradeable on site

Fully configurable using EnerVista™ 469 software

Parameterization, monitoring, and diagnostics via PC interface

Environmental and Reliability Features

Optional conformal (three-proof) coating

Suitable for humid, dusty, or corrosive environments

Industrial-grade design for long service life and high reliability

Typical Applications

The Multilin 469 relay is designed for protection and management of medium- and high-voltage motors (typically ≥ 100 kW), including:

Petrochemical and refinery compressors

Power plant fans and auxiliary motors

Metallurgical rolling mills

Water treatment and pumping stations

Large industrial process motors

Key Advantages

Comprehensive electrical, thermal, and mechanical motor protection in one device

Flexible I/O and communication options for easy system integration

Advanced diagnostics and event recording for faster fault analysis

On-site firmware upgrade and intuitive configuration via EnerVista

Optional conformal coating for harsh industrial environments

GE SR469-P5-HI-A20｜Motor Protection Relay｜